Propellor (Propeller?)

Potatoe, Patatoe.... Propellor, Propeller?

If you search Airmaster propeller, you will find their website - propellor.com

But Merriam Webster says its spelt PROPELLER, not OR.  Oh well, must be a downunder thing.

I received my BEAUTIFUL 4 blade Airmaster prop in September.  I have been busy on the cowl (and getting covid), so other than making sure I had all the bits I haven't touched it.

This is what it will look like when its done... hopefully.  (Picture is of Tracy Ross's awesome UL 520T powered Sportsman).

2 blades per box (blades are Sensinch).  Spinner, hub, controller and wiring in the other.

Spinner and hub (assembled, and bolted to the transport board).  Wont take this apart until I need it.

2 of the 4 blades.  Overall prop diameter is 74".

Wiring.  All plug and play.

Prop controller in the panel temporarily to check for any fitment issues.

In August I had a chance to go for a flight with Tracy.  Overall the prop / engine combo is super smooth.  The prop controller has lights at the top that tells you what its doing.

• The prop controller has 4 'modes':  Take Off, Climb, Cruise and Feather.  The first 3 have target RPM's that are set.  In Tracy's case, take off is set for 2650 RPM, and cruise is 2500.  Not sure what he has Climb set to.
• During runup he flipped the switch from auto to manual, and cycled the prop.  There is a manual couse / fine switch. I am going to have to build a bracket and mount it under the throttle.
• All in all, the prop and its operation was very anticlimactic.  It just worked.

From a fitment perspective, the spinner lines up with the forward face of the engine crank flange, so that is where I have it set.  Visually inspecting the spinner, that is spot on.

Hopefully it all fits.  I am going to have to reprofile the cowl to line up correctly with the spinner due to its larger diameter.

Schematics and Wiring

I have done a fair bit of wiring in my time.  I don't consider myself an expert, but it almost always works. Where I struggle is on making it look 'right'.  I want this one to be 'right'.

You need a wiring diagram - that is a must.  However, I am also building a wire run list in Microsoft Excel.  The two go hand in hand.

The wire run list show you extreme detail on each wire.  Where is it from, where does it go, what does it connect to, wire size, color, etc.  The schematic gives you most of those details.  The nice thing about excel is you can filter and search.

Below is an example of the autopilot servo wiring.

And here is the drawing from Advanced.

Note:  I do not have a yaw servo, but the ACM supports it.

Where the Advanced drawing is correct, I am simply using that.  No point reinventing the wheel.  However where it needs modification, I am drawing from scratch.

I looked around for quite awhile for a good schematic software.  The basic requirements:

• Multi platform.  If I ever sell the plane, someone will need to be able to edit the drawings.
• PDF output compatible (this is pretty universal)
• Decent parts library
• Easy to use.
• Preferably free (or low cost)
• Supported.  Did not want to find a piece of free software that goes away or is not supported in 5 years (as an example).

After lots of hunting and frustration, a fellow builder put me onto QElectroTech.  On a scale of 1 to 10, I give it about a 7.  It is by no means perfect - but its free, and does most things that you need.  It has a pretty good parts library, and you can make your own parts (what the software calls elements).  Its multi platform as well.  It does take a bit of getting used to.

Below is my main power distribution (not yet finished).

And my control stick wiring (this one is pretty much finished).

Bottom line:  The documentation is going to be a lot of work - especially making the 'elements' where needed.  But it is necessary and worthwhile.

Front and Rear Seats

I have been lacking motivation lately.  Coming of 5 back to back race weekends, I am rather burnt out.

I need to do some serious organizing of the wires behind the panel.  Everything tells me its not that bad, but I think it is.

So I took the afternoon, and put my front seats in... but that means taking out the header tank, installing the forward tunnel covers, putting in the floor boards, then the seat pan tubs, then the seat rails.  Well I did, and It looks pretty good

All of the tubs and tunnels had been sitting in the basement literally gathering dust.

Also pushed it outside today to give the shop a good cleaning.  Interesting to see the perspective on the 'long nose sportsman'.  I think I will call her Pinocchio.

Going to be hard to see over the nose with a longer cowl, extended gear legs, and bigger tires.  The below pic is not 100% accurate as the front of the cowl is not in the right spot - its about 1" too high.

This was taking from my eye level, sitting in the plane.

Rear seats and front / rear carpet.

UL Throttle Assembly

Nothing is easy, especially when you put a non standard engine on.

First off, here is the UL throttle assembly from their website.  To me, this looks like a bike cable.  We used something similar on the quarter midgets.  There is a ball on the end that hooks into the forward end of the throttle butterfly linkage, and a groove that it sits in.  This system is reliant on the spring on the throttle body to pull the cable forward.

I talked to Ray, and yes - this is what he uses on his plane.  Has not had a problem to date.  But, when i asked him about using this with a standard push pull throttle (he has a quadrant style), he had zero solution.

But he did mention that Zenith has a bracket for this.  Well, there is a UL powered Zenith at my airport that just flew.  I had some pictures of the install, and I emailed Greg today as well and he sent me another pic.  Here are both...

It appears that the 4 cylinder UL's throttle body is much farther forward (look at his air cleaner... it fits between the throttle body and the ring gear - that wont work with ours).

The mount on the engine used for lifting the engine is used to mount the throttle.  Also, the throttle cable is moved to the right of center.

I think the solution here is to use a throttle cable with a 10-32 male end, and get a 10-32 heim joint, with a spacer between them.  I have a throttle cable I can use for mock up, and ordered these from amazon.  Will see how it works out.  If I find a satisfactory solution, I will order the correct length mcfarlane throttle with one of their heim joints.

I am away starting wednesday for pretty much the next 3.5 weeks.  

Cowling and Extension - Part III

 In part I and II, the cowling was extended ~11".  Also, I dished and reinforced the top.  Now its onto the sides.

Going to do the sides one at a time.  Left side below.

2 laminates.  ~0.5" and 1" with peel ply on top.  Didnt get all the way to the bottom... going to deal with that separately after I figured out what I am going to do with the air exit ramp.  This time I chose to do it on the airplane - partially because I could, but mainly because it is holding in in the correct shape.

Its a bit messier then I would like, and will take a bit more cleaning up.

Right side next.

First round of filler on the top.  Mixture of resin, cabosil, and glass bubbles.  The large filler areas on the sides is where the aluminum picked up.  But there are 4 layers of glass under, and 2 on top, so I am not worried.

Sanded the top down to even everything out, then a 2nd round of filler and more peel ply (good thing I bought a roll.

I got most of the low spots on the first round.  

First round of filler on the left side of the lower cowl.

The transition from the side to the bottom had the largest gap.  Planning on a single layer of glass here to stiffen it up and prevent cracking.  Doing everything on this piece on the airplane to keep it in the correct shape and not sitting on a bench.

Going to give the right side another day before sanding.

Slowly getting everything built up to look right.

Going to do a little bit more on the top and lower sides, then moving on to the exit air ramp extension.  Planning to use a similar aluminum mold.

Lots of work travel coming up in October and November, so progress will be slow for the next bit.